surrealdb_core/sql/statements/
delete.rs

1use crate::ctx::Context;
2use crate::dbs::{Iterator, Options, Statement};
3use crate::doc::CursorDoc;
4use crate::err::Error;
5use crate::sql::{Cond, Output, Timeout, Value, Values};
6use derive::Store;
7use reblessive::tree::Stk;
8use revision::revisioned;
9use serde::{Deserialize, Serialize};
10use std::fmt;
11
12#[revisioned(revision = 2)]
13#[derive(Clone, Debug, Default, Eq, PartialEq, PartialOrd, Serialize, Deserialize, Store, Hash)]
14#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
15#[non_exhaustive]
16pub struct DeleteStatement {
17	#[revision(start = 2)]
18	pub only: bool,
19	pub what: Values,
20	pub cond: Option<Cond>,
21	pub output: Option<Output>,
22	pub timeout: Option<Timeout>,
23	pub parallel: bool,
24}
25
26impl DeleteStatement {
27	/// Check if we require a writeable transaction
28	pub(crate) fn writeable(&self) -> bool {
29		true
30	}
31	/// Process this type returning a computed simple Value
32	pub(crate) async fn compute(
33		&self,
34		stk: &mut Stk,
35		ctx: &Context<'_>,
36		opt: &Options,
37		doc: Option<&CursorDoc<'_>>,
38	) -> Result<Value, Error> {
39		// Valid options?
40		opt.valid_for_db()?;
41		// Create a new iterator
42		let mut i = Iterator::new();
43		// Assign the statement
44		let stm = Statement::from(self);
45		// Ensure futures are stored
46		let opt = &opt.new_with_futures(false).with_projections(false);
47		// Loop over the delete targets
48		for w in self.what.0.iter() {
49			let v = w.compute(stk, ctx, opt, doc).await?;
50			i.prepare(stk, ctx, opt, &stm, v).await.map_err(|e| match e {
51				Error::InvalidStatementTarget {
52					value: v,
53				} => Error::DeleteStatement {
54					value: v,
55				},
56				e => e,
57			})?;
58		}
59		// Output the results
60		match i.output(stk, ctx, opt, &stm).await? {
61			// This is a single record result
62			Value::Array(mut a) if self.only => match a.len() {
63				// There was exactly one result
64				1 => Ok(a.remove(0)),
65				// There were no results
66				_ => Err(Error::SingleOnlyOutput),
67			},
68			// This is standard query result
69			v => Ok(v),
70		}
71	}
72}
73
74impl fmt::Display for DeleteStatement {
75	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
76		write!(f, "DELETE")?;
77		if self.only {
78			f.write_str(" ONLY")?
79		}
80		write!(f, " {}", self.what)?;
81		if let Some(ref v) = self.cond {
82			write!(f, " {v}")?
83		}
84		if let Some(ref v) = self.output {
85			write!(f, " {v}")?
86		}
87		if let Some(ref v) = self.timeout {
88			write!(f, " {v}")?
89		}
90		if self.parallel {
91			f.write_str(" PARALLEL")?
92		}
93		Ok(())
94	}
95}
surrealdb_core/sql/statements/delete.rs

surrealdb_core/sql/statements/
delete.rs
